Hadith: The Prophet Muhammad (sal Allahu alayhi wa salaam) said:
“Whoever builds a mosque with the intention of seeking Allah’s pleasure, Allah will build for him a place in Paradise.”
Sahih Al-Bukhai, Hadith #441 | Vol.1 | Agreed Upon

Whatever you give or spend in the way of Allah will be returned to you in manifold increase. Allah, the most Bountiful and the most Loving, commends:

Lend unto God a goodly loan. Whatever good you shall forward on your behalf you shall find it with God, as better and richer in reward. [al-Muzzammil 73: 20.]

Be generous, therefore, for whatever you spend on yourself is only for your temporary sustenance while whatever you spend in the way of Allah is an investment in your future for which will provide everlasting sustenance. Seek to invest in others for your own benefit with whatever Allah has endowed you.

Allah says: Of their wealth take alms to purify and sanctify them. [at-Tawba 9:103.] Furthermore: He that spends his possessions [on others] so that he might grow in purity. [al-Layl 92: 18.]